HTTP Input and Output

HTTP input/output character encoding conversion may convert
binary data also. Users are supposed to control character
encoding conversion if binary data is used for HTTP
input/output.

Nota:

If enctype for HTML form is
set to multipart/form-data and
mbstring.encoding_translation is set to On
in php.ini the POST'ed variables and the names of uploaded files
will be converted to the internal character encoding as well.
However, the conversion isn't applied to the query keys.

HTTP Input

There is no way to control HTTP input character
conversion from a PHP script. To disable HTTP input character
conversion, it has to be done in php.ini.

When using PHP as an Apache module, it is possible to
override those settings in each Virtual Host directive in
httpd.conf or per directory with .htaccess. Refer to the Configuration section and
Apache Manual for details.

HTTP Output

There are several ways to enable output character encoding
conversion. One is using php.ini, another
is using ob_start() with
mb_output_handler() as the
ob_start callback function.